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Chapter 6 Packet Filtering
Configuration
This chapter covers IP packet filtering configuration of the SMC7301TA.
Note:
Packet filtering is a sophisticated feature that can substantially impact
your SMC7301TA operation. Therefore be sure that you fully understand the
descriptions in this chapter before you start to configure and use this feature.
This is because if you make any mistakes, it may produce drastic and
potentially undesired results.
IP Packet Filtering Overview
The SMC7301TA already provides you with many different ways to
ensure the security of your data in your local environment. For example, the
concept of single IP address and private networking means devices on your
network can access the Internet, but not vice versa. This feature has proven
to be useful and effective to most users. However, for some users, additional
security requirements may exist, which can be satisfied by this packet filtering
feature.
Packet filtering is a security feature that allows you to s electively pass or
throw away data traffic between your local LAN and the wide area network
(For example, the Internet). Specifically, it allows you to define:
each and every IP packet to be inspected to determine if it should be
allowed to be transmitted over a WAN interface, or alternatively,
each and every IP packet to be inspected to determine if it should be
disallowed from being transmitted over a WAN interface.
Due to the conflicting nature of allow and disallow, only one of the above
two choices can be made for each WAN interface. After the choice is made,
you can define selection rules to “select” which packets will be allowed (or
disallowed). Each selection rule consists of:
